Lock



H. BIEMER May 12, 1942.

y LOCK Filed Feb. 14, 1940 Patented May 12, 1942 .Lockl 5' l. AHeinrichl'ienier, London, England.' Y I Application-February'14, 1940, seraiNb.- l318,921 In Great Britain February 15, 1939 (ci. v-n64) .-1

2 Claims.

This invention relates to locks, and more particularly to locks of the type comprisinga lock- Y ing cylinder rotatable in a lock casing, said looking cylinder being provided with tumbler-strips each having an aperture therein, which are operated on the insertion through the apertures lof a key with correspondingly profiled edges in known manner so as tofrearrange the strips with their ends within the confines of the locking cylinder and enables same to rotate in the lock casing.

The aim ofthe present invention is to provide an improved construction of locking cylinder in which the tumbler strips are prevented from falling out of said cylinder on withdrawal of the key during assembly of the tumblers in said cylinder during manufacture.

To this end, in accordance with the present invention, the locking cylinder is provided with rods extending longitudinally therethrough and passing through apertures in the tumbler strips,

said apertures being of suicient size in relation to the diameter of the rods to allow the tumblers suncient play to full their normal function, but preventing them from'falling right out of the cylinder on withdrawal of the key under the circumstances hereinbefore specified.

In one embodiment of the invention, the longitudinally extending rods are in the form of a guide for the key-bit, and therefore take the form of two parallel strips extending through the key apertures in the tumbler strips.

Alternatively the rods need not serve as a guide for the key-bit, inv which case they are preferably passed through apertures in the tumbler strips which are separate from the key-bit apertures.

The construction of the present invention may be modied in several ways to facilitate the assembly of the tumblers in the locking cylinder.

In one modcation, the retaining rods do not extend right through the cylinder, but a small gap is left between one end of the rods and the end plate of the locking cylinder, suicient to enable the tumblers to be slipped into position. This gap can be suitably closed after assembly is complete.

In another modification, the end plate of the locking cylinder is detachable, thus enabling the tumbler strips to be inserted thereinto from the rear, whereupon the detachable portion is secured to the locking cylinder for example by screwing.

When the retaining rods do not function as a guide for the key-bit, in order nevertheless to facilitate the centering of said bit on insertion into the lock, the rear wall or end plate of the locking cylinder is provided with a recess, the shape of which corresponds to the profile of the key-bit, and with which the end of said-bit engages.

In order that the invention may be more clearly understood, reference is made to the accompany- Ying drawing, which illustrates diagrammatically and by way of example, two embodiments thereof and in which- Fig. 1 is a plan View partly in section, of one embodiment;

Fig, 2 is a section on the line II-II of Fig. 1;

Fig. 3 is a plan view partly in section of part of another embodiment; and

Fig. 4 is a section on the line IV-IV of Fig. 3.

In Fig. 1, I is a rotatable locking cylinder, on one end of which is mountedv the peg 5 adapted to actuateA a locking bar in known manner on rotation of the cylinder l.v

2 denotes the tumbler strips, `the shape of which is apparent from Fig. 2. Aguide 3 is provided for'V thekey-bit, consisting of 2 parallel rods orV strips extending longitudinally through the locking cylinder I, Vand secured in the lower end of the cylinder in any well known manner,

as forexample by a driving fit (not shown), the inner sides of said strips being proled vin ac cordance with the p role of the key-bit. Said guide 'alsopasses through the apertures in the tumbler strips 2, and while allowing them suflicient play to fullil their normal function, it prevents them dropping out of the locking cylinder on withdrawal of the key-bit.-

To enable the tumbler strips to be assembled in the locking cylinder, the guide does not eX- tend right through the cylinder, but a gap is left between one end of the guide 3 and the end plate of the cylinder, enabling the tumbler strips to be slipped over the guide. This gap is closed after assembly by the locking plate 4.

In Fig. 3, 6 denotes the locking cylinder, and

` 1 the tumbler strips, the shape of which is shown inA Fig. 4. It will be seen that each strip is provided with two apertures 8 in the shape of slits on either side of the central aperture, flat rods 9 passing through the slits 8 and being secured in the lower end of the cylinder in a similar manner to the rods 3 of Fig. 1`. Said rods prevent the tumblers from falling out of the cylinder on withdrawal of the key, although it will be seen that the relative sizes of said slits and of the rods 9 is such as to allow the tumblers considerable play.

simultaneously functioning as a guide for the keybit, said rods extending longitudinally into the lock cylinder and passing through apertures in said plate tumblers, whereby the tumbler strips are prevented from falling out of said cylinder Y during the assembly of the tumblers in said cylinder during manufacture, the length of said rods being such as to leave a space between the ends of the rods and the adjacent end of the slot in the cylinder in which the tumblers' may be inserted to enable them to .be :assembledn'on the l rods.

2. In a lock containing aislotted locking cylf 2L 1 g aa'saee i inder rotatable in a casing, with straight-sided plate tumblers adapted to pass through the slots and operable in known manner by a profiled key, the provision of two parallel proled rods simultaneously functioning as a guide for the key-bit, said rods extending longitudinally into the locking cylinder and passing through apertures in said plate tumblers, whereby the tumbler strips areprevented from falling out of said cylinder during the assembly of the tumblers in said cylinder during manufacture, the length of said rods being such as to leave a space between the ends of the rods and the'adjacent end of the j Vslot in the cylinder in which the tumblers may be inserted to enable them to be assembled on the rods, and a locking plate forvretainlng said tumblers on s aidrrods,

` HEINRICH BIEMER. 

